This is a rendering of the inlet structure near Horace, N.D., looking downstream from the dam. / Image credit: Fargo-Moorhead Diversion Authority.2 / 3

Tim Mahoney3 / 3

FARGO — Minnesota regulators have decided they must conduct a supplemental environmental review of the revised Fargo-Moorhead Diversion, and now local officials hope permit approval for the $2.4 billion project can come this fall.

The Minnesota Department of Natural Resources, which must grant a permit for a dam on the Red River in order for the project to proceed, notified the Diversion Authority that it needs more information about the impacts of the modified project under its permitting process.

In another diversion development on Wednesday, May 2, the federal judge in Minneapolis who is hearing a legal challenge seeking to block the diversion ruled that requests to allow work on two construction projects can continue.

U.S. District Judge John Tunheim gave permission to allow work on a ring dike to protect Oxbow, N.D., and to provide flood protection near downtown Fargo. The Minnesota Department of Natural Resources had agreed to allow work at the two locations in a stipulation with the Diversion Authority.

"To us it's a good sign," Fargo Mayor Tim Mahoney said of Tunheim's order allowing the work to continue. The court approval reflects the cooperation between the Diversion Authority and the Minnesota DNR on the flood project, he said.

"I'm really excited," Mahoney said of Tunheim's order, granting a request made last month.

Meanwhile, Mahoney and Moorhead Mayor Del Rae Williams said the Minnesota DNR's decision to go ahead with an environmental review of the revised diversion project was expected, and still could enable a permit to be issued this fall, perhaps in September or October.

"We didn't think anything was going to happen in April or May," in terms of a decision on a permit for the revised project, Williams said. "It was going to take time to do the permit review. I'm not really surprised."

In March, the Diversion Authority released a plan that altered the alignment of the embankment for the flood project. It's needed to contain water that will pool temporarily during severe floods to allow a controlled release of floodwaters through the diversion and Red River as it winds through Fargo-Moorhead.

As modified, the project shifts the embankment north, downstream, with the result being more water from the diversion's dam will be impounded in rural Cass County, sparing upstream areas of Richland and Wilkin counties, which oppose the project.

The Minnesota DNR's environmental review will coincide with a review of the revised project by the U.S. Army Corps of Engineers. To the extent possible, Minnesota officials will rely on technical data developed by the corps and will try to dovetail their review.

"There's no need to reinvent wheels," Williams said. "That's good."

A permit decision by September or October "is not out of the question," she said. "It really does seem to be going kind of on a pace that we thought. This is fine."

Mahoney agreed.

The judge's order means the city of Fargo can open bids on floodwall work in mid-May, start construction in June, with completion in two years, said Nathan Boerboom, an engineer for the city. The work is on the Second Street floodwall south of Main Avenue.

Patrick Springer first joined the reporting staff of The Forum in 1985. He can be reached by calling 701-241-5522. Have a comment to share about a story? Letters to the editor should include author’s name, address and phone number. Generally, letters should be no longer than 250 words. All letters are subject to editing. Send to letters@forumcomm.com